TRACKING THE PHENOLIC PROFILE OF LICURI (Syagrus coronata) ALONG PROCESSING: FROM ALMOND TO PARTIALLY DEFATTED CAKE AND SUPERCRITICAL CO₂-EXTRACTED OIL

Licuri (Syagrus coronata) is a palm native to the Brazilian semi-arid region with a lipid-rich almond, yet the fate of its phenolic compounds during oil extraction remains poorly understood. Phenolic compounds are relevant for their antioxidant and bioactive properties, associated with health benefits. The objective of this study was to track the phenolic profile of licuri along processing, from the almond to the partially defatted cake and, finally, to the oil obtained by supercritical carbon dioxide (scCO₂) extraction under the highest-yield condition (50 °C and 350 bar; 53% yield), assessing process selectivity. Procyanidins B1 and B2, catechin, epicatechin, and protocatechuic and p-hydroxybenzoic acids were quantified in duplicate by UPLC-MS.

In the almond, epicatechin was the major compound (35.97 µg g⁻¹), followed by catechin (31.12 µg g⁻¹), procyanidin B1 (28.74 µg g⁻¹), procyanidin B2 (25.79 µg g⁻¹), protocatechuic acid (8.80 µg g⁻¹) and p-hydroxybenzoic acid (7.76 µg g⁻¹). In the cake, epicatechin (41.06 µg g⁻¹), procyanidin B1 (33.26 µg g⁻¹), procyanidin B2 (30.74 µg g⁻¹) and p-hydroxybenzoic acid (9.15 µg g⁻¹) increased relative to the almond, catechin increased slightly (33.08 µg g⁻¹), and protocatechuic acid remained practically unchanged (8.63 µg g⁻¹), with no compound decreasing. The total phenolic content rose from 138.2 µg g⁻¹ in the almond to 155.9 µg g⁻¹ in the cake, reflecting the partial removal of oil. Conversely, the scCO₂ oil contained only traces of procyanidins B1 and B2 and epicatechin (≤ 0.13 µg g⁻¹), while catechin and the hydroxybenzoic acids were not detected. Under these conditions, the high fluid density enhances the solvating power of CO₂, but its low polarity and lack of hydrogen-bonding capacity limit the solubilization of polyhydroxylated, more polar and higher-molecular-weight compounds, such as dimeric procyanidins, which remain in the solid matrix.

These results demonstrate the high selectivity of scCO₂ extraction: the oil is practically free of phenolic compounds, whereas the partially defatted cake retains them and can be valorized as a phenolic-rich food ingredient. This solvent-free, integral use of licuri adds value to agroextractivist production chains and contributes to UN Sustainable Development Goals 2, 3 and 12 and to the FAO four betters: better production, nutrition, environment and life.